Process of treating petroleum residues



C. S. PALMER. PROCESS OF TREATING PETROLEUM RESIDUES, &c.,

APPLICATION FILED AUG.29| I9]!- Patented Aug. 12, 1 919. 4

wumawwmmm I| lwlllll I l|l| IIIIIIIIIIIIIL ma i a TEMPERATURESI I I II9Q 200 2") 22) 80 210 250 260 270 230 290 300 anja CHARLES S. PALMER,OF PITTSBURGH, PENNSYLVANIA;

PROCESS OF TREATING PETROLEUM BESEDUES, M

Specification of Letters Patent.

Patented Aug. 12, 1919.

Original application iiled June 12, 1918, Serial No. 103,288. Dividedand this application filed August :39,

1917. Serial No. 188.707.

and useful Improvements in Processes of Treating Petroleum Residues,&c., of which the following is a specification.

My invention relates particularly to improvements in making varioushydrocarbon compounds of the aromatic series from crude petroleum,petroleum residues, heavy oils resulting from the distillation ofbituminous coal, and the like, and from the residuum resulting from themanufacture of oil gas, including any other source of heav liquid orsolid hydrocarbons from whic volatile hydrocarbons may be derived. Amongthe various materials treated are mineral, vegetable or animal tars,"pitches, asphalts, resins, ums, oils, paraflins, which are eithernon-v0 atile, partially volat1le, or volatile with difliculty, and alsoother mineral, vegetable or animal materials or compounds capable ofacting in a similar manner to the above.

The usual process of cracking or decomposing the aforementionedcompounds consists 1n subjecting the same to a hi 11 degree of heatwhereby they are partia ly decomposed and disintegrated into volatilecompounds. These are simultaneously distilled with the result that moreor less residual coke or carbonaceous residues are produced. In allinstances the operation was carried on under extremely hlghtemperatut-es, while the pressure was at or below two atmospheres.

My rocess consists of aradical and fundamental series of changes whichresult in an equilibrium peculiar to each particular case and the natureof the compounds produced, which will naturally vary according to thematerial operated upon, the time, the degree of heat and the pressureapplied thereto.

The basis of my invention resides in the fact that other things beingequal, non-volatile materials will undergo radical chan es in makingvolatile products, the more vo atile ones requiring the hi her pressureprovided, suflicient heat is a ded to satis the various chemical andphysical requirements.

The important features of my prpcess consist: (1) n thecompleteseparation of the so-called -crackmg from the step of distilling, theformer being carried out at high pressure, usually in excess of fouratmospheres, while the latter is conducted preferably at or belowatmospheric pressure.

(2) In conducting the cracking in heavil constructed digesters capableof Withstand ing enormous pressures, while supplying sufficient heatthereto to liquefy, to volatilize,

to create a predetermined pressure, to furnish' latent heat ofvolatilization, and to furnish the requisite endothermic heat offormation. (3) In utilizing the pressure element to direct and controlthe reaction. Quite contrary to usual expectations, the greater thepressure the greater will be the decomposition, recomposition andpolymericases special reactions may require a greater lapse of timeaccording to the end in View.

In carrying out thesaid Process in accordance with m invention, theresidues to be treated usual y being materials substantiallynon-volatile below 300 C., are first introduced into a steam jacketedreservoir wherein the same is melted, and thence are introduced into ahigh pressure digester wherein it is subjected to the requisiteconditions of temperature and pressure necessary for carrying out theprocess, the means for producing the requisite temperatures andprossures, 8 m, being indicated in the drawings accompanying thisspecification and forming a part thereof.

In the drawings, Figure 1 is an elevation chiefly in section of anapparatus adapted for this purpose. Fig. 2 represents a curve 7illustrating the process in operation.

Referrin to the drawings, the reference numeral 1 esignates a tank orreservoir provided with a cover, 2, a steam-jacket 3, a

drainage pipe 4, and a steam inlet pipe 5.

An outlet plpe 6, provided with a valve 7, is connected by a pipe 8,provided with a valve 9, with a digester 10. The digester which isconstructed preferably of half-inch steel, isprovided with a cap orclosure 11,

securely packed in the usual manner, a manhole 12, and pipe-extensions13, 11, and-21 respectively. A jacket 15 preferably as shown beingprovided with steam coils 16, completely surrounds the said digester,openings being provided in both the digester and the said jacket for theinsertion of a pressure-gage 17 and a thermometer 18. Thepipe-extensions Hand 21 project through the jacket 15 and are providedwith a check valve 19 and a stop-cock 20 respectively. These extensionsare connected with piping 22 and 23 to a still 24, of well knownconstruction, provided with the usual steamcoils 25, inlet 26, vaporoutlet 27, and thermometer 28. l

The residues treated in the above described apparatus as actuallypractised, consisted in so far as could be determined from the specificgravity and melting points, of mixtures of hydrocarbons of the paraiiinseries, (l H -iof the range C H, to C H uring treatment, which usuallydid not exceed a few minutes, the pressures gradually increased with thetemperature, according to the curve shown in Fig. 2, until a pressure of130 pounds was reached, when there was apparently a sudden conversion ofthe materials present into more volatile compounds which caused a rapidincrease in the pressures as shown without the indication of any greatincrease in temperatures. Since the heat was being uniformly appliedthereto, it is apparent that at this pressure there was a largeabsorption of heat which prevented any noticeable indication of anIncrease in temperature. \Vhile in the specific example above given thepressures constantly increase throughout the operation, it is obviousthat in many instances it may be desirable to vary the pressure and subject the material to an alternating high and low pressure. To accomplishthis purpose or to prevent an excessive increase in pressure, I providethe check-valve 19, which may be adjusted for any degree of pressuredesired, whence upon an increase of the pressure above that to which thevalve is set, the vapors from the digester will pass over into the still24. a

While steam coils are preferably utilized owing to the accuracy withwhich the tem perature can be adjusted, especially when super-heatedsteam is used, as is the case when operating as above described, it isobvious that without departing from the spirit of m invention thedigester may be subjecte to the direct or indirect action of gases froma regenerator, muflle or other furnace.

The products obtained from the above treatment, as actually carried out,upon fractional distillation gave results substantially as follows:

Up to 100 (3., about 5% distillate;

and 150 C. about 10% and 200C. about 10% and 250 C. about 20% and 300 C.about 1092 uniformly yielded from 65% to 75% of volatile matters attemperatures varying from 100 C. to 300 C. Moreover, when the residuesof one treatment were mixed with the residues of another batch ortreatment and were again treated, there was no accumulation ofnon-volatile residue. In fact a non-volatile residue remaining from thelast fraction of one treatment even if subsequently treated alone, wouldoften be decomposed in a manner substantially similar to that ofuntreated residues when treated alone, since each treatment would haveits quota of undecomposed residue ac cording to the equilibriumestablished. Accordingly, each residue when re -treated would decomposeexactly as though 'it had not been previously treated, as thedecomposition takes place at the appropriate equilibrium and long beforeall the residue is transformed. a

.In Fig. 2 the curve shown illustrates the process when operating up to300 C. and the pressures ranging from 30 pounds up to 160 pounds, and infact experiments show, that when operating even up to 100 pounds, thedecomposition, recom osition and polymerization, other things eingequal, is directly dependent upon the increase of pressure, and that theradical transformation into many new compounds having new moleculararrangements,'does not be in much below five or six atmospheres incependent of the temperature. On the other hand, the said experimentsindicate that at pressures ranging from 20 to 30 atmospheres theformation of new compounds takes place with great rapidity. In all casesthe volatile products of decomposition increase with more pressure attemperatures from 200 C. to 300 C. This indicates it is not merely thehigh temperatures, but rather moderate temperature and high pressurethat governthe decomposition and determine the result.

.As a specific example: when operating with heavy, waxy. tarry or pitchymaterials at temperatures ranging from 200 C. to 325 C. and underpressures of from 60 to the original; At pressures ranging from 150pounds up to 300 and 400 pounds per s uare inch, and at temperatures offrom 2 to 325 (3., from 75% to 90% of the materials were converted intovolatile products. These products were in all cases subjected to dis-.

tillation, at or below atmospheric pressure, 80 arately from thedigesting operation.

Vhile the external'pressure is not so effective as the temperature indetermining the equilibrium in cases where there is no change in thenumber and nature of the molecules, yet in such cases as hereindescribed, and usually at temperatures apparently approximating criticaltemperature, the external pressure appears to be the efiicient factor indetermining the character of the resulting compounds.

Thus if one starts with a mixture consisting, for example, of paraffinof. the C Hfifl series] it is obvious that if it is attempted tosplitthe said mixture up into lighter molecules of the same series that therewill be enough hydrogen to satisfy but a part of thepossiblenewmolecules that may be formed. The result will be theformation of compounds as C,,H,,,, or even O H, C H C &c. Now theseunsaturated, so to spea possible compounds, might include the trueunsaturated derivatives of the ethylene and wet lene series, althoughnormally this is rare y the case, or of the benzene, toluene,naphthalene, anthracene, etc, groups which occasionally happens to bethe case; or'of' the poly-methylene series, the naphthenes as di-, tri-,tetra penta-, hex'a-methylenes, etc., and their derivatives, as is oftenand usually the case. Again, if heavy bone oils are so treated, similarnitrogen-carbon bodies may be produced according to the equilibriumunder the conditions of operation. In the case of other'mineral,vegetable or animal 'materials treated, the results will vary accordingto their chemical composition, and the products of decomposition thatare pos sible, but always the reaction will be understood to take placeaccording to the rule that, (given heat enough to liquefy, heatsuflicientto volatilize, heat suflicient to pro duce the desiredpressure, and sulficient heat in addition to furnish the endothermicintermolecular heatrequired for the vari-' ossibilities) the greater ousnew. so-called arger the percentage of the pressure, the

volatile products. In this connection the poly-methylenes,

scribed thedigesting operation can be alter- V nately subjected to' arelatively high and then a low pressure during the continuousapplication of heat to the substance being treated. In this mannerwithout removing the materials'from the digester I am enabled to carryout in a single process the com lete. decomposition in so far as the 4equi ibrium permitsof complete decomposition, without stop ing theprocess, and thus in many-cases t e said process is renf dered .moreefficient and economical.

Throughout the claims the term aromatic as used, includes not onlybenzene, toluene, naphthalene, anthrace'ne, etc., pyridin, -quinolin,&c., but also the cyclic and hydrobenzenes, including naphthenes and thehydrobenzenes referred to bein such compounds as C,,H,,H,, C,,H,H,, and,H,,H,. This application is my co-pending application No. 103,288, filedJune 12, 1916, which is in turn adivision of an ori inal application No.360975 filed March 2n 1907, Patent No. 1,187,380 of June 13th, 1916.Having thus described my invention, what I claim and desire to secure byLetters Patinto more volatile products, said temperatures being belowthat point at which suf ficient carbonization' oocursto substantiallyinterfere with such transformation, and said digesting being conductedvy'ith the treated materials being alternately subjected to high and lowpressure during the digesting riod, such high pressure being principa lly self-produced by the evolved volatilized filed as 'a division ofcompounds undiluted by added aqueous 'va- Pots and such alternating low.pressure being produced by the release of the evolved volatiliz edcompounds until the desired predetermined low pressure 1s obtained.

. 2. The rooess of treating crude petroleum and petro eum residues ofthe. paraflin series to, increase the yield of volatl e compounds abovethat normally obtainable therefrom,

which consists in digesting the same in a confined space under apressure in excess of' eight atmospheres, said pressure beingprincipally autogenous, and at a temperature in excess of 200 C., for atime sufliciently long to induce transformation of the major portion ofsaid materialstreated into more volatile products, said temperaturesbeing below that point at which sufiicient carbonization occurs tosubstantially interfere with such transformation, and said digestinbeing conducted with the treated materia s being alternately subjectedto high and low pressure during the digesting aeriod, such high pressurebeing principal y self-produced by the evolved volatilized compoundsundiluted by added aqueous vaporsand such alternating low pressure beingproduced by the release of the evolved volat-ilized compounds until thedesired predetermined low pressure is obtained.

3. The process of treating crude petroleum and petroleum residues of theparallin series to increase the yield of volatile compounds above thatnormall; obtainable therefrom, which consists in digesting the same in aconfined space under a pressure in excess-of four atmospheres and notexceeding 400 pounds )er square inch, said pressure being principallyautogenous, and at a tem erature in excess of 200 C., for a time suciently long to induce transformation of the major portion of saidmaterials treated 'into more volatile products, said temperatures beingbelow that point at which sufiicient carbonization occurs tosubstantially interfere with such transformation, and said digestingbeing conducted with the treated materials being alternately subjectedto high and low pressure during the digesting period, such iigh pressurebeing principall selt-pio' duced by the evolved volatilized compoundsundiluted by added aqueous vapors and such alternating low pressurebeing produced by the release of the evolved volatilized compounds untilthe desired predetermined low pressure is obtained.

In witness whereof, I have hereunto set my hand at the cit ofPittsburgh, county of Allegheny and btate of Penn., this 27th day ofAugust, 1917.

CHARLES S. PALMER.

It is hereby certified that Letters Patent No. 1,313,009, grantedAugusta, 1919', upon the application of Charles S. Palmer, ofPittsburgh, Penneylvania, for an improvement in Processes of TreatingPetroleum Residues, &c.," were erroneously issued to the inventor, saidPalmer, as miner of said invention, whereas said Letters Patent shouldhave been issued to Standard Oil Company, a corpmfion qf Indiana, saidcorporation being assignee of the entire interest in said invention, asshown by 'the records of assignments in this Oflice; and that the saidLetters Patent should be read with this correction therein that the samemay conform to the record of the case in the Patent Office.

Signed and sealed this 2nd day of September, A. D., 1919.

[sent] M. H. COULSTON,

. Acting Commissioner of Patents. Cl. 196-25.

